{
  "bibcode": "2015GCN.17738....1K",
  "body": "D. A. Kann (TLS Tautenburg), T. Kruehler (ESO Chile), S. Klose (TLS\nTautenburg) and J. Greiner (MPE Garching) report:\n\nWe obtained a photometry sequence in BVRIz with VLT FORS2 of the optical \nafterglow (Varela et al., GCN # 17729, # 17732; Perley, GCN # 17733;\nLittlejohns et al., GCN # 17736) of the short GRB 150423A (Swift-638808,\nPagani et al., GCN # 17728).\n\nObservations started on April 23, 2015, 08:02:19 UT, 94 minutes after the\nGRB. Seeing was 1\".0 and airmass was 1.7.\n\nThe afterglow is clearly detected in BVR. Analysis of Iz is pending.\n\nWe find Rc = 22.8 +/- 0.1 in the first image (calibrated against SDSS\nstandard stars transformed to Rc) and find it fades by approximately 0.4\nmagnitudes in the course of an hour (see also Perley, GCN # 17733;\nLittlejohns et al., GCN # 17736).\n\nWe are indebted to Jonathan Smoker and Fernando Selman for VLT UT1 support.",
  "circularId": 17738,
  "createdOn": 1429820449000,
  "email": "kann@tls-tautenburg.de",
  "subject": "GRB 150423A: VLT detection",
  "submitter": "Alexander Kann at TLS Tautenburg  <kann@tls-tautenburg.de>",
  "eventId": "GRB 150423A"
}